(Reuters)–Two Boston policemen were in critical condition early on Thursday after they were shot in a gunfight with a man who was shot dead by other police officers, police said.

Other officers responding to the incident on the city’s East Side shot and killed the man who was armed with an assault rifle and wearing a ballistic vest, Police Department Commissioner William Evans told a news conference.

"Domestic calls are probably the most volatile. You never really know what you are walking into," he said.

The shooting took place inside a house in the Orient Heights neighborhood at about 11 p.m. local time, the Boston Police Department tweeted.

One of the officers was shot several times and the other officer was shot once or twice. Both were in "extremely critical" condition at a local hospital, Evans said.

Nine other officers, who had dragged their wounded colleagues out of the house, were being treated for minor injuries and trauma at another hospital, he said.

Police did not identify the gunman or the wounded officers, one of whom had been with the police department for about 28 years and the other for about 12 years, police said.

(Reporting by Brendan O’Brien in Milwaukee; Editing by Louise Ireland)